http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Hossain, Shakhawat,Lee, Insu,Kim, Sun Min,Kim, Kwang-Yong Elsevier 2017 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.327 No.-
<P><B>Abstract</B></P> <P>A novel design is presented for a chaotic micromixer using two-layer serpentine crossing microchannels. The performance of the micromixer was analyzed both numerically and experimentally. The numerical analysis was performed using three-dimensional Navier-Stokes equations with a convection–diffusion model for the species concentration in a Reynolds number range of 0.2–120. An experimental model of the micromixer was fabricated by soft lithography with polydimethylsiloxane (PDMS). Two working fluids, water and dye-water mixture were used for numerical analysis except for the experimental validation of numerical results. Both the numerical and experimental analyses confirm that the micromixer achieves a high level of mixing over a wide range of Reynolds numbers through splitting, enlarging, recombination, and folding mechanisms. The micromixer showed over 95% mixing throughout the tested range of Reynolds number. Especially, about 99% mixing was achieved at Reynolds numbers less than ten. Thus, the proposed micromixer can be used in microfluidic systems which require fast mixing at low Reynolds numbers.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Experimental and numerical analyses of a novel micromixer with two-layer crossing channels were performed. </LI> <LI> The micromixer showed at least 96% mixing throughout a Reynolds number range (0.2–120). </LI> <LI> At low Reynolds numbers (0.2–10), the micromixer showed about 99% mixing at the exit. </LI> <LI> The proposed micromixer showed lower pressure drop than TLCCM for Re larger than 10. </LI> </UL> </P>
Numerical Study on Mixing Performance of Straight Groove Micromixers
Hossain, Shakhawat,Kim, Kwang-Yong Korean Society for Fluid machinery 2010 International journal of fluid machinery and syste Vol.3 No.3
Numerical analyses have been performed to investigate the effects of geometric parameters of a straight groove micromixer on mixing performance and pressure drop. Three-dimensional Navier-Stokes equations with two working fluids, water and ethanol have been used to calculate mixing index and pressure drop. A parametric study has been carried out to find the effects of the number of grooves per cycle, arrangement of patterned walls, and additional grooves in triangular dead zones between half cycles of grooves. The three arrangements of patterned walls in a micromixer, i.e., single wall patterned, both walls patterned symmetrically, and both walls patterned asymmetrically, have been tested. The results indicate that as the number of grooves per cycle increases the mixing index increases and the pressure drop decreases. The microchannel with both walls patterned asymmetrically shows the best mixing performance among the three different arrangements of patterned walls. Additional grooves confirm the better mixing performance and lower pressure drop.
Reaz Akter Hossain,Saha Shimul,Roy Chanchal Kumar,Wahab Md Abdul,Will Geoffrey,Amin Mohammed A.,Yamauchi Yusuke,Liu Shude,Kaneti Yusuf Valentino,Hossain Md. Shahriar,Firoz Shakhawat H. 나노기술연구협의회 2022 Nano Convergence Vol.9 No.10
This work reports the rational design of MnOx nanorods on 3D crushed reduced graphene oxide (MnOx/C-rGO) by chemical reduction of Ni-incorporated graphene oxide (GO) followed by chemical etching to remove Ni. The resulting MnOx/C-rGO composite synergistically integrates the electronic properties and geometry structure of MnOx and 3D C-rGO. As a result, MnOx/C-rGO shows a significantly higher specific capacitance (Csp) of 863 F g−1 than MnOx/2D graphene sheets (MnOx/S-rGO) (373 F g−1) and MnOx (200 F g−1) at a current density of 0.2 A g−1. Furthermore, when assembled into symmetric supercapacitors, the MnOx/C-rGO-based device delivers a higher Csp (288 F g−1) than MnOx/S-rGO-based device (75 F g−1) at a current density of 0.3 A g−1. The superior capacitive performance of the MnOx/C-rGO-based symmetric device is attributed to the enlarged accessible surface, reduced lamellar stacking of graphene, and improved ionic transport provided by the 3D architecture of MnOx/C-rGO. In addition, the MnOx/C-rGO-based device exhibits an energy density of 23 Wh kg−1 at a power density of 113 Wkg−1, and long-term cycling stability, demonstrating its promising potential for practical application.